Last Call Review of draft-ietf-dnsop-avoid-fragmentation-15
review-ietf-dnsop-avoid-fragmentation-15-tsvart-lc-kuehlewind-2023-10-22-00
review-ietf-dnsop-avoid-fragmentation-15-tsvart-lc-kuehlewind-2023-10-22-00
This document has been reviewed as part of the transport area review team's ongoing effort to review key IETF documents. These comments were written primarily for the transport area directors, but are copied to the document's authors and WG to allow them to address any issues raised and also to the IETF discussion list for information. When done at the time of IETF Last Call, the authors should consider this review as part of the last-call comments they receive. Please always CC tsv-art@ietf.org if you reply to or forward this review. Thanks for the document; it's straight-forward but probably important to write down. I have two editorial comments and one request: 1) I would really recommend including "IP" in the document title to be absolute clear about the scope. So renaming to "IP Fragmentation Avoidance in DNS". 2) This sentence is really hard to read: "TCP avoids fragmentation using its Maximum Segment Size (MSS) parameter, but each transmitted segment is header-size aware such that the size of the IP and TCP headers is known, as well as the far end's MSS parameter and the interface or path MTU, so that the segment size can be chosen so as to keep the each IP datagram below a target size." Maybe split it into two sentences: "TCP avoids fragmentation by segmenting data into packets that are smaller than or equal to the Maximum Segment Size (MSS). As for each transmitted segment the size of the IP and TCP headers is known, the IP packet size can be chosen to keep it below the other end's MSS and path MTU." 3) In R8 you mention a timeout. Is it already anywhere specified how to set such a time for DNS retransmissions? If so, I think a reference would be useful. If not, more guidance is need to avoid network overload.